l-Acjg'.a,-.  /8k 

&.  S.  Librae?.  (J 
:ES"EKVE. 


connecticut 
Agricultural  Experiment  Station 

NEW  HAVEN,  CONN. 


BULLETIN  186,  FEBRUARY,  1915. 


ENTOMOLOGICAL  SERIES,  No.  21. 


The  Gypsy  Moth. 


Cc 


S 

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ho,)? 


Figure  i. — Female  and  male  gypsy  moths.     Natural  size. 

CONTENTS. 
Page 


Officers  and  Staff 2 

The  Gypsy  Moth 3 

Importance  Abroad 3 

Appearance  and  Spread  in  the 

United  States 4 

Discovery  in  Connecticut, 5 

Stonington 5 

Wallingf  ord 7 

Present  Infested  Area 9 

Federal  Quarantine 9 


Page 

Injury  and  Food  Plants 11 

Methods  of  Spread 12 

Habits  and  Life  History 14 

Description 16 

Natural  Enemies 17 

Imported  Parasites 18 

Control  Measures 19 

Creosoting  Egg-Clusters 19 

Banding  Trees 20 

Spraying 22 

Summary. 22 


The  Bulletins  of  this  Station  are  mailed  free  to  citizens  of  Connecti- 
cut who  apply  for  them,  and  to  others  as  far  as  the  editions  permit. 


CONNECTICUT  AGRICULTURAL  EXPERIMENT  STATION. 

OFFICERS  AND  STAFF. 


BOARD    OF    CONTROL 

His  Excellency,  Marcus  H.  Holcomb,  ex-officio,  President. 

Prof.  H.  W.  Conn,  Vice  President Middletown 

George  A.  Hopson,  Secretary Wallingford 

E.  H.  Jenkins,  Director  and  Treasurer New  Haven 

Joseph  W.  Alsop Avon 

Wilson  H.  Lee Orange 

Frank  H.  Stadtmueller Elmwood 

James  H.  Webb Hamden 


Administration.  E.   H.  Jenkins,   Ph.D.,   Director  and    Treasurer. 

Miss  V.  E.   Cole,   Librarian  and  Stenographer. 
Miss  L.   M.  Brautlecht.   Bookkeeper  and  Stenographer. 
William  Veitch,  In  charge  of  Buildings  and  Grounds. 

Chemistry. 

Analytical  Laboratory.   John  Phillips  Street,    M.S.,  Chemist  in  Charge. 
E.  Monroe  Bailey,  Ph.D.,  C.  B.   Morison,  B.S. 
C.  E.  Shepard,  G.  L.   Davis,  Assistants. 
Hugo  Lange,  Laboratory    Helper. 
V.  L.   Churchill,  Sampling  Agent. 
Miss  E.  B.  Whittlesey,  Stenographer. 


Proteid  Research 
Botany. 

Entomology. 

Forestry. 

Plant  Breeding. 
Vegetable  Growing. 


T.  B.  Osborne,  Ph.D.,  Chemist  in  Charge. 
Miss  E.  L.  Ferrt,  M.  S.,  Assistant. 

G.  P.  Clinton,  Sc.D.,   Botanic. 
E.  M.  Stoddard,  B.S.,  Assistant  Botanist. 
Miss  E.   B.   Whittlesey,    Herbarium    Assistant. 
G.   E.   Graham,   Genera!    Assistant. 

W.   E.   Britton,   Ph.D.,    Entomologist;    State  Entomologist. 

B.  II.  Walden,  B.Agr.,   First  Assistant. 
Q.  S.  Lowry,  B.Sc,   I.  W.   Davis,  B.Sc, 

M.   P.  Zappe,  B.S.,   Assistants. 
Miss  F.  M.  Valentine,  Stenographer. 

Walter   O.   Filley,    Forester:    also  State    Forester 

and  Slate    Forest    Fire    Warden. 
A.    E.    Moss,    M.    P.,    Assistant   Station    Forester. 
Miss  E.  L.  Avery,  Stenographer. 

Donald   F.  Jones,   B.S.,   Plant    B> 

C.  D.   Hubbell,   .1  ssi slant. 

Howard  F.  Huber,  B.S. 


THE  GYPSY  MOTH. 

Porthetria  dispar  Linn. 
By  W.  E.  Britton,  State  Entomologist. 

For  nearly  twenty-five  years  the  State  of  Massachusetts  has 
been  engaged  in  an  attempt  to  control  one  of  the  most  destructive 
insects  known — the  gypsy  moth.  In  spite  of  these  early  efforts 
the  pest  kept  on  spreading  and  soon  reached  other  states  where  it 
has  also  caused  great  damage.  At  the  time  of  this  writing,  the 
gypsy  moth  occurs  in  all  of  the  New  England  States,  having  just 
been  found  in  two  towns  in  Vermont.  The  entire  area  of  Rhode 
Island  is  infested  as  is  also  the  eastern  end  of  Connecticut,  more 
than  half  of  Massachusetts  in  the  eastern  portion,  the  southern 
half  of  New  Hampshire,  and  the  southwestern  portion  of  Maine. 
Each  of  these  states  has  appropriated  and  expended  many  thou- 
sands of  dollars  in  suppressing  this  insect,  and  the  cost  in  Massa- 
chusetts extends  into  the  millions. 

Since  1906,  when  Congress  first  made  an  appropriation  for  this 
work,  the  Bureau  of  Entomology  has  co-operated  with  the  states 
in  controlling  the  gypsy  moth. 

This  insect  was  discovered  in  Connecticut  at  Stonington  in  1906, 
and  at  Wallingford  in  1909 — two  isolated  infestations  which 
have  since  been  exterminated.  In  the  spring  of  1913,  just  after 
the  eggs  hatched,  the  minute  caterpillars  were  carried  a  long  dis- 
tance probably  by  a  gale  and  scattered  egg-clusters  have  since 
been  found  in  eighteen  towns  in  the  eastern  portion  of  Connecti- 
cut. 

Since  1906  the  State  has  expended  more  than  $31,000.00  in 
work  against  the  gypsy  and  brown-tail  moths,  and  during  this 
time  the  Federal  authorities  have  expended  more  than  $30,000.00 
for  labor  alone,  in  moth  suppression  in  the  State  of  Connecticut. 

Importance  of  the  Gypsy  Moth  Abroad. 

The  gypsy  moth  occurs  in  Central  and  Southern  Europe,  North- 
ern Africa,  and  throughout  Southern  and  Central  Asia,  including 
Japan  and  Ceylon.  On  the  European  continent  the  insect  becomes 
abundant  at  intervals  and  causes  great  damage  in  certain  areas. 


4         CONNECTICUT    EXPERIMENT    STATION,    BULLETIN    NO. 

In  general,  however,  it  is  held  in  check  by  its  natural  enemies  and 
is  nowhere  such  a  serious  pest  as  it  has  proven  to  be  in  this  coun- 
try. It  is  now  considered  a  rare  insect  in  England.  As  most  of 
the  earlier  collections  contained  plenty  of  examples  of  the  g 
moth,  while  the  more  recent  ones  do  not,  it  is  fair  to  assume  that 
it  was  formerly  rather  abundant  there. 

Appearance  and  Spread  in  the  United  States. 

According"  to  the  best  obtainable  information,  the  gypsy  moth 
was  first  brought  into  this  country  in   1869,  or  thereabouts,  by 
Mr.  L.  Trouvelot,  an  artist  and  astronomer  who  was  inter  - 
in  silk  culture.     In  order  to  overcome  a  wilt  disease  or  "flacherie" 
then  playing  havoc  in  some  silk  worm  establishments,  he  tried  to 
cross  the  silk  worm  with  certain  other  species  to  obtain  a  hardier 
or  more  resistant  race  of  silk  worms.     Among  other  silk  spinning 
caterpillars  in  their  various  stages  which  he  imported  from  France 
for  this  purpose  were  some  egg-masses  of  the  gypsy  moth.     Some 
of  the  caterpillars  escaped  accidentally  from  the  breeding  cages 
at  his  home,  27  Myrtle  Street,   Medford,  Mass..  and   though  he 
searched  for  them  and  published  a  notice  at  the  time,  the  a 
was  soon  forgotten.     The  insect  was  not  seen  for  years,  but  !> 
1889  had  become  a  serious  pest  in  this  same  locality. 

The  town  of  Medford  first  raised  a  sum  of  money  for  its  conl 
and  in  1890  the  State  Legislature  made  its  first  appropriation  for 
moth  work.  At  first  only  a  small  area  was  infested,  and  had  the 
knowledge  and  experience  which  we  now  possess  then  been  availa- 
ble, the  pest  might  perhaps  have  been  exterminated.  But  methods 
had  to  be  worked  out,  men  trained,  the  insect  studied,  and  as  mam 
of  the  earlier  methods  finally  were  shown  to  be  ineffective,  the 
insect  was  not  eradicated.  Finally  after  ten  years,  the  Massa- 
chusetts legislature  in  1900,  refused  to  make  further  appropria- 
tions and  the  state  suppression  work  ceased.  At  that  time  the 
infested  area  covered  359  square  miles  in  the  vicinity  ol  Boston. 
For  five  years  no  slate  work  was  carried  on,  though  many  private 
owners  and  probably  some  municipalities  controlled  the  pesl  on 
the  land  under  their  jurisdiction.  In  [905  the  gypS)  moth  had 
spread  and  multiplied  and  become  such  a  nuisance  that  state  con- 
trol work  was  resumed  and  has  since  been  continued:  but  in  10113. 
instead  of  covering  359  square  miles,  the  pest  bad  spread  and  then 
covered  an  area  of  2.224  square  miles,  and  extended  from  beyond 


THE  .GYPSY    MOTH!     DISCOVERY    IN    CONNECTICUT.  5 

the  New  Hampshire  line  south  to  Buzzard's  Bay,  and  westward 
as  far  as  Marlborough.  A  large  colony  had  also  become  estab- 
lished at  Providence,  R.  I.  It  had  no  doubt  spread  considerably 
beyond  these  limits,  for  it  was  soon  found  in  New  Hampshire  and 
later  in  Connecticut  and  in  Maine. 

In  addition  to  the  infested  areas  mentioned  on  page  3,  isolated 
infestations  have  been  found  as  follows :  one  at  Lenox,  Stock- 
bridge  and  Great  Barrington,  Mass. ;  Greenfield,  Mass. ;  Spring- 
field, Mass. ;  Stonington,  Conn. ;    Wallingford,    Conn. ;    Geneva, 


GYPSY   MOTH 
QUARANTINE 


Fig.  2.     Map  of  Connecticut  showing  area  quarantined  on  account 
of  gypsy  moth. 


N.  Y. ;  Mount  Kisco,  N.  Y. ;  Rutherford,  N.  J. ;  and  near  Cleve- 
land, Ohio.  The  three  last  named  infestations  were  discovered 
during  the  year  1914.  These  separate  infestations  have  all  been, 
nearly  if  not  quite,  exterminated. 

Discovery  in  Connecticut. 

Stonington. 

In  July  1905,  two  female  moths  were  taken  and  two  males  seen 

at  Stonington  by  Mr.  Ernst  Frensch,  a  collector  of  insects.     Later 

egg-masses  were  found.     Mr.   Frensch  communicated  with  this 


6         CONNECTICUT    EXPERIMENT    STATION,    BULLETIN'    NO.     186. 

office  in  February  j  906,  and  the  writer  visited  Mr.  Frensch,  saw 
his  specimens  and  the  egg-clusters.  The  center  of  the  infesta- 
tion was  apparently  in  some  brush  growing  around  the  pond 
near  the  velvet  mill  on  the  eastern  side  of  the  village.  These  egg- 
clusters  were  destroyed  and  the  brush  cut  and  burned.  Later  other 
egg-clusters  were  discovered  on  apple  and  other  trees  in  the  vicin- 


Figure  3.- — Diagram  showing  life  history  of  Gypsy  moth. 


ity  and  some  distance  away.     Altogether  less  than  a  square  mile 
was  the  greatest  area  infested  at  Stonington. 

In  the  summer  of  1906  about  10.000  caterpillars  wore  destroyed 
at  Stonington.  The  number  grew  smaller  each  year  until  ion 
when  none  were  found.  It  is  not  known  how  the  gyps)  nl"tn 
reached  Stonington.  but  it  may  have  been  brought  accidentally 
from  Eastern  Massachusetts  on  some  goods  shipped  to  the  velvet 


THE    GYPSY    MOTH!     DISCOVERY    IN    CONNECTICUT.  7 

mill  or  its  employees,  or  it  may  have  been  brought  directly  from 
Europe.  The  complete  records  of  this  infestation  are  given  in 
the  following  table : 

Record  of  Gypsy  Moths  Destroyed  at  Stonington. 
Year  Egg-masses  Caterpillars  Cocoons 

1906  73  10,000  47 

1907  118  2,936  200 

1908  73  2,560  44 

1909  6  98  o 

1910  1  146  1 

1911  3  00 

1912  o  00 

Though  we  believe  that  this  infestation  had  already  been  eradi- 
cated the  work  was  continued  in  1913.  Late  in  the  caterpillar 
season  a  nearly  mature  caterpillar  was  found  on  one  of  the  banded 
trees.  More  men  were  employed,  the  entire  region  searched,  and 
altogether  five  caterpillars  and  one  pupa  were  found  in  Stonington. 
It  seemed  to  be  a  reinfestation,  and  this  view  was  later  confirmed 
by  Federal  scouts  who  found  the  following  winter,  scattered  egg- 
clusters  in  nearly  all  of  the  eastern  border  towns  of  the  State.  A 
force  of  men  under  the  supervision  of  Mr.  Irving  W.  Davis  has 
been  scouting  this  winter  in  Stonington  and  in  North  Stonington 
but  no  egg-clusters  have  been  found. 

Wallingford. 

The  writer's  first  intimation  that  a  gypsy  moth  colony  existed  in 
Wallingford  came  on  the  morning  of  Tuesday,  December  14, 
1909,  when  Mr.  B.  H.  Walden,  first  assistant  entomologist,  called 
attention  to  an  item  in  the  Wallingford  News  of  a  New  Haven 
daily  paper  issued  the  night  before.  The  paper  stated  that  egg- 
clusters  of  this  insect  had  been  discovered  in  the  borough,  naming 
some  of  the  streets  and  stating  that  the  Warden  would  soon  have 
men  destroy  the  eggs.  Mr.  Walden  at  once  visited  Wallingford 
and  found  plenty  of  evidence  of  the  presence  of  the  pest.  Men 
employed  by  this  office  were  immediately  set  at  work  creosoting 
the  eggs  and  searching  for  more. 

The  presence  of  the  gypsy  moth  in  Wallingford  was  first  no- 
ticed by  Mr.  Leslie  A.  Brown,  a  designer  of  silverware  employed 
by  the  R.  Wallace  &  Sons  Mfg.  Co.  Mr.  Brown  noticed  an  egg- 
cluster  on  the  trunk  of  a  tree  while  on  his  way  to  his  work.  He 
had  formerly  lived  in  Newburyport,  Mass.,    where    he    became 


8  CONNECTICUT    EXI'KRIMHNT    STATION,    BULLETIN    NO.     [86. 

familiar  with  the  gypsy  ninth  and.  therefore,  recognized  the 
at  sight. 

Of  course,  it  is  not  known  how  the  pest  was  brought  to  Wal- 
lingfordj  but  probably  egg-clusters  were  carried  there  unnoticed 
on  a  crate  or  packing  box.  The  worst  infested  section  was  in  the 
rear  of  some  stores  north  of  Center  Street,  and  these  stores  receive 
manv  shipments  of  goods  from  Eastern  Massachusetts. 

Less  than  a  square  mile  of  territory  was  infested,  the  area  ex- 
tending from  the  railroad  east  to  Fair  Street,  and  from  Ward 
Street  northward  to  Christian  Street.     More  than  8,000  egfff-clus- 


F 1  cure  4.- — Egg-mass  on  bark. 
Natural  size. 


Figure  5. — Cj 
pillar.  Natural  size. 


ters  were  found  and  destroyed  that  winter  and  nearly  9,000  cater- 
pillars the  following  summer.  For  three  years  Mr.  Donald  J. 
Caffrey  had  charge  of  the  work,  which  was  done  so  carefully  and 
thoroughly  that  no  caterpillars  or  egg-masses  have  been  found 
there  since,  The  statistics  of  the  Wallingford  infestation  are 
siven  in  the  following'  table: 


Record  of  Gyps-*  Moms  Destroyed  \i  Wali  lngford. 


Year 
19 10 
[9 1  1 
[912 

1913 
[914 


Egg-masses 

8,234 

23 

5 
2 

0 


rpillai 
8,936 

1.551 
26 


O  ic<  ions 
96 

15 
1 

o 
o 


the  gypsy  moth:   discovery  in  connecticut.  9 

Present  Infested  Area. 

On  account  of  the  limited  State  funds  which  were  all  needed  in 
Stonington  and  Wallingford,  and  in  the  brown-tail  moth  work,  it 
was  fortunate  that  Connecticut  could  have  the  co-operation  of  the 
Federal  authorities  in  scouting  the  eastern  end  of  the  State.  All 
of  the  towns  along  the  eastern  border  have  been  searched  by  Fed- 
eral scouts,,  except  a  portion  of  the  previously  infested  area  in 
Stonington.  At  first  the  Federal  scouts  examined  only  the  trees 
in  orchards  and  along  the  roadsides.  They  found  scattered  egg- 
clusters,  one  or  two  in  a  place,  in  the  towns  of  Thompson,  Wood- 
stock, Putnam,  Pomfret,  Killingly,  Voluntown,  North  Stoning- 
ton, Stonington  and  Groton.  Those  found  in  Stonington  were  in 
the  country  north  of  the  area  previously  infested.  Then  the  men 
searched  the  woodland  and  found  many  more  egg-clusters.  Later  a 
search  was  made  in  adjoining  towns,  some  of  which  were  found 
to  be  infested.  At  the  time  of  this  writing  the  following  eighteen 
towns  may  be  called  infested,  though  in  some  of  them  no  cater- 
pillars were  found  during  the  summer  and  no  egg-clusters  found 
there  this  winter: 

Windham  County.  New  London  County. 

Thompson  Voluntown 

Woodstock  North  Stonington 

Pomfret  Stonington 

Putnam  Groton 

Killingly  Sprague 

Eastford  Lisbon 

Hampton  Griswold 
Brooklyn 
Canterbury 
Plainfield 
Sterling 

Federal  Quarantine. 

The  Federal  law  establishing  the  Federal  Horticultural  Board, 
became  operative  October  ist,  1912,  and  authorized  the  Board  to 
establish  and  maintain  quarantines,  of  course  preceded  by  due 
notices,  hearings,  etc.  The  first  gypsy  moth  quarantine  became 
effective  August  1,  191 3,  and  did  not  include  any  towns  in  Con- 
necticut, for  at  the  time  of  the  hearing  in  June  none  of  them  were 
known  to  be  infested  except  Stonington,  where  the  gypsy  moth 
colony  was  thought  to  be  exterminated,  and  Wallingford  where 


Figi  R]    6. — Egg-clusters  on  trunk  of  apple  tree. 


THE    GYPSY    MOTH!     INJURY    AND    FOOD    PLANTS.  II 

only  traces  of  the  pest  remained.  At  that  time  both  these  colonies 
were  reg-arded  as  isolated  infestations.  A  year  later,  however, 
the  quarantine  lines  had  to  be  revised,  and  at  present  include  the 
following  ten  Connecticut  towns ;  Thompson,  Woodstock,  Put- 
nam, Pomfret,  Brooklyn,  Killingly,  Voluntown,  North  Stonington, 
Stonington  and  Groton.  Next  year  the  quarantine  limits  must 
again  be  revised  to  include  Eastford,  Hampton,  Canterbury,  Plain- 
field,  Sterling,  Griswold,  Sprague,  Lisbon,  and  such  other  towns 
as  are  found  to  be  infested  prior  to  the  time  of  the  hearing.  These 
towns  and  the  present  quarantine  limits  are  shown  on  the  accom- 
panying map  figure  2. 

All  nursery  stock,  lumber,  telephone  poles,  piles,  railroad  ties, 
etc.,  as  well  as  quarry  products,  must  now  be  inspected  and  certi- 
fied by  a  Federal  inspector  before  they  can  be  shipped  from  the 
quarantined  area  to  points  outside  this  area. 

Injury  and  Food  Plants. 

The  damage  caused  by  the  gypsy  moth  consists  in  stripping 
trees,  shrubs  and  other  plants  of  their  leaves  by  the  caterpillars. 
Formerly  it  was  supposed  that  the  caterpillars  would  attack  al- 
most any  kind  of  foliage,  ash,  being  perhaps,  the  most  nearly  im- 
mune of  any  of  our  broad-leaved  deciduous  trees.  In  the  publi- 
cation, "The  Gypsy  Moth"  by  Forbush  and  Fernald,  is  given  a 
list  of  several  hundred  food  plants,  containing  nearly  all  the  com- 
mon cultivated  ones.  But  more  recent  investigations  at  the 
parasite  laboratory,  Melrose  Highlands,  Mass.,  conducted  under 
the  direction  of  Mr.  A.  F.  Burgess,  show  that  the  caterpillars  in 
their  first  and  second  stages  are  not  able  to  live  on  some  of  these 
plants  even  though  they  may  feed  on  them  in  later  stages  of  devel- 
opment. For  instance,  though  the  caterpillars  in  their  later  stages 
will  feed  upon  pine,  and  have  killed  large  areas  of  pine  mixed  with 
hard  wood  in  Massachusetts,  they  must  have  some  deciduous 
foliage  for  food  in  their  first  and  second  larval  stages.  Consid- 
ering the  matter  from  this  standpoint  it  seems  quite  possible  to 
cut  out  all  other  growth  leaving  solid  stands  of  pine  or  other  coni- 
fers which,  with  only  slight  protection,  may  escape  destruction. 
By  the  use  of  tanglefoot  on  the  trunks  of  the  trees  around  the 
margins  of  such  an  area,  little  damage  will  result. 

In  slight  infestations  the  insects  are  nearly  always  found  on  old 
apple  trees.     They  are  partial  to  fruit  trees,  willow,  oak,  poplar 


12       CONNECTICUT    EXPERIMENT    STATION,    BULLETIN    NO. 

and  rose,  but  when  the  caterpillars  are  abundant,  food  becomes 
increasingly  scarce  and  they  will  feed  upon  a  great  man}-  different 
trees  and  plants. 

Methods  of  Spread. 
As  the  insect  passes  about  three-quarters  of  its  life  cycle,  includ- 
ing the  winter,  in  the  egg-stage,  there  is  a  long  period  from  late 
Jul}"  until  the  following"  May,  when  the  egg-clusters  may  be 
transported  on  packing  boxes,  crates,  freight  cars,  vehicles,  nurs- 
ery stock,  lumber,  quarry,  or  other  products,  which  have  remained 


Figure  7. — Gypsy  moth  caterpillars      Natural  size. 

for  a  time  in  July  or  August  in  the  infested  region.  This  is  es- 
pecially true  if  these  products  have  been  stored,  stacked,  or  al- 
lowed to  remain  where  gypsy  moths  were  abundant  at  the  time 
when  the  eggs  are  laid.  The  egg-clusters  are  seldom  noticed  or 
recognized  by  the  men  handling  these  materials  and  might  In- 
shipped  long  distances  into  various  states.  This  is  the  reason  for 
establishing  a  quarantine,  thus  preventing  all  shipments  going 
out,  unless  inspected  and  certified  by  a  Federal  inspector.  This 
method  of  spread  will  probably  account  for  the  isolated  infesta- 
tions at  Stonington  and  Wallingford  and  most  of  those  in  other 
states. 


THE    GYPSY    MOTH!     METHODS    OF    SPREAD. 


13 


The  caterpillars  when  nearly  grown,  and  especially  if  very  num- 
erous, crawl  about  in  search  of  food  or  a  place  in  which  to  pupate, 
and  sometimes  board  trains,  trolley  cars,  automobiles,  etc.,  and 
may  be  carried  long  distances.  The  insect  may  also  be  trans- 
ported in  the  pupa  and  adult  stages  but  as  the  females  do  not  fly, 
and  as  the  cocoons  are  usually  in  holes  or  protected  places  and  as 
such  short  periods  are  passed  in  these  stages,  there  is  much  less 
danger  of  their  spreading  than  in  the  egg  and  caterpillar  stages. 


Figure  8. — Egg-clusters  and  pupae  on  inside  of  loose  hickory  bark. 

Wind-spread  is  probably  accountable  for  most  of  the  extension 
of  the  large  area  of  infestation.  This  extension  has  been  more 
rapid  toward  the  north  and  east  than  in  other  directions.  When 
the  caterpillars  first  hatch  from  the  eggs,  they  are  of  course,  very 
small  and  are  covered  with  hairs,  some  of  which  are  bulbous  and 
known  as  aerostatic  hairs.  Whether  or  not  this  is  their  real  func- 
tion, it  is  true  that  these  first-stage  caterpillars  are  carried  long 
distances  by  strong  winds  occurring  at  this  time.  Mr.  Burgess 
had  a  large  screen  placed  on  the  Isles  of  Shoals,  seven  miles  away 


14      CONNECTICUT    EXPERIMENT    STATION,    BULLETIN    NO.    186. 

from  the  nearest  infested  trees.  This  screen  was  covered  with 
tanglefoot  and  caught  several  young"  caterpillars.  According  to 
the  Federal  men,  this  wind-spread  explains  the  scattered  infesta- 
tions through  Eastern  Connecticut  in  the  spring  of  1913.  Of 
course,  if  the  wind  blows  toward  the  center  of  the  infested  area 
no  harm  will  result,  but  if  it  blows  outward,'  the  area  may  be 
greatly  increased  or  extended. 

Habits  and  Life  History. 

The  young  caterpillars  hatching  from  the  eggs  about  May  1st. 
feed  and  hide  upon  the  leaves,  spinning  down  on  silken  threads 


Figure  9. — Old  pupa  skins  under 
fence  rail.      Natural  size. 


Figure  10. — ATachinidfly  Tachina 
mella  reared  from  a  gypsy  moth  pupa 
at  Wallineford.  Three  times  enlarged. 


when  disturbed.  They  usually  feed  at  night  and  often  rest  on 
the  underside  of  the  leaves  during  the  day  where  their  presence 
is  apt  to  be  overlooked.  They  molt  five  or  six  times  and  gradually 
increase  in  size,  reaching  maturity  early  in  July.  Caterpillars 
molting  five  times  usually  develop  into  males,  and  those  molting 
six  times  become  females,  according  to  Mosher  and  Webber*  who 
have  carried  on  many  experiments  and  observations  at  the  I  rypsy 
Moth  Parasite  Laboratory  at  Melrose  Highlands,  Mass.  During 
this  entire  larval  period  the  caterpillars  are  hairy,  dark  in  general 
color  and  some  show  a  predominating  tint  of  brown  and  others 


*  Journal  Economic  Entomology,  Vol.  7.  page  368,  [914. 


THE    GYPSY    MOTH!     HABITS    AND    LIFE    HISTORY 


IS 


are  gray.  There  is  much  variation  in  size,  the  largest  caterpillars 
being  nearly  three  inches  long  (probably  molting  six  times)  ;  most 
of  them,  however,  are  between  two  and  two  and  one-half  inches. 
From  the  time  they  are  half-grown,  they  hide  during  the  day  time 
in  crevices  in  the  bark,  in  cavities,  or  in  some  other  dark  place, 
presumably  to  escape  their  natural  enemies,  and  are  found  on  the 
leaves  only  at  night.  When  fully  grown  they  crawl  about  to  find  a 
protected  place  in  which  to  make  their  cocoons.  The  pupa  stage 
lasts  from  ten  days  to  two  weeks  when  the  adult  emerges. 


Figure  ii. — Female  laying  egg-cluster  on  baric  .of  tree. 
Natural  size. 

The  male  moth  is  generally  brown  in  color  and  flies  about  even 
in  the  day  time.  The  female  is  nearly  white,  with  rather  incon- 
spicuous cross  markings  of  brown  and  black,  and  is  larger  than 
the  male.  The  female  has  a  heavy  body  and  does  not  fly  but  rests 
on  the  trunk  or  branches  of  trees,  sides  of  buildings  and  walls, 
and  in  such  places  she  lays  her  eggs.  The  adults  take  no  food 
and  live  only  a  short  time.  It  is  in  the  egg-stage  that  most  of  the 
time  is  spent,  the  eggs  being  found  about  August  ist,  until  the 
following  May,  a  period  of  nine  months. 


l6     connecticut  experiment  station,  bulletin  no.   186. 

Description. 

Egg. — The  egg  is  globular,  white  or  transparent,  and  slightly 
more  than  i  mm.  in  diameter.  An  average  of  between  400  and 
500  eggs  are  laid  together  in  a  cluster  and  covered  with  the  buff 
hairs  from  the  bod}'  of  the  moth.  The  egg-clusters  vary  greatly 
in  size  and  shape,  but  roughly  speaking  they  are  oval,  about  two- 
thirds  as  broad  as  long,  and  look  and  feel  like  a  piece  of  chamois 
skin.  Some  large  egg-clusters  are  two  inches  or  more  in  length, 
and  small  ones  may  be  not  more  than  half  an  inch,  but  in  Con- 
necticut the  average  length  is  about  an  inch.  Egg-clusters  are 
shown  in  figures  4  and  6. 

Larva. — The  young  larvae  resemble  the  mature  ones  closely 
enough  so  that  they  may  be  easily  recognized  when  seen.     The 


* 


Figure  12. — Female  moth. 
Natural  size. 


Figure  13. — Male  moth. 
Natural  >"ize. 


fully-grown  caterpillar  has  a  dusky  ground  color,  finely  marked 
with  darker  spots  giving  it  a  granular  appearance  ;  sometimes  it 
has  a  marked  brown  tint,  and  sometimes  it  is  decidedly  gray. 
There  is  a  lighter  stripe  along  the  back  with  a  row  of  tubercles  on 
each  side  of  it,  two  on  each  segment.  From  the  head  the  first 
five  pairs  of  tubercles  are  blue;  the  remaining  six  pairs  are  brick- 
red.  The  colors  show  more  prominently  as  the  larvae  approach 
maturity.  There  is  usually  a  lighter  lateral  stripe  between  the 
row  of  tubercles  and  the  spiracles.  The  ventral  surface,  legs  and 
pro-legs  are  light  grayish  brown.  Mead  is  dark'  brown  marked 
with  yellow.  Each  segment  bears  six  tubercles  arranged  in  a 
transverse  row,  each  tubercle  hearing  a  tuft  of  hairs.  The  larvae 
vary  from  two  to  three  inches  in  length  and  are  shown  in  fig- 
ures 5  and  7. 


THE    GYPSY    MOTH!     NATURAL    ENEMIES.  1 7 

Pupa. — The  pupa  is  almost  naked  but  is  loosely  inclosed  by  a 
few  strands  of  silk.  It  is  reddish-brown  in  color  with  a  few 
short  light  brown  hairs  around  the  spiracles  and  across  the  thor- 
acic and  abdominal  segments  ;  the  apical  extremity  by  which  it  is 
fastened  also  bears  a  tuft  of  these  hairs.  The  pupae  usually  occur 
in  clusters  in  protected  places,  such  as  under  fence  rails  near  the 
posts,  crotches  of  trees,  cavities,  etc.  This  stage  is  shown  in  fig- 
ures 8  and  9. 

Adult. — The  female  is  dirty  creamy  white  with  rather  faint, 
transverse  brown  markings,  and  having  a  wing-spread  varying 
between  two  and  two  and  one-half  inches.  The  abdomen  is  heavy, 
cylindrical,  and  covered  with  buff  hairs.  The  male  is  smaller  and 
much  darker  in  color ;  he  has  a  wing-spread  of  about  one  and  one- 
half  inches,  with  a  small  and  pointed  abdomen.  The  color  is 
brown  varying  greatly.  Antennas  in  both  sex  are  pectinate,  nar- 
row and  black  in  the  female,  broader  and  light  brown  in  the  male. 
The  female  is  shown  in  figure  12,  the  male  in  figure  13  and  both 
sexes  in  figure  1. 

Natural  Enemies. 

Every  species  of  insect  has  its  natural  enemies.  The  gypsy 
moth  has  several  which  are  native  to  this  country  but  none  of  them 
are  effective  in  holding  it  in  check.  One  of  the  large  ground 
beetles  Calasoma  scrutator  Fabr.,  known  as  the  "searcher"  or 
"caterpillar  hunter"  was  rather  common  under  the  burlap  bands  at 
Stonington  and  at  Wallingford,  and  was  observed  eating  the  cater- 
pillars. One  of  these  beetles  in  captivity  devoured  137  gypsy  cat- 
erpillars in  thirteen  days,  an  average  of  more  than  ten  per  day. 
Calosoma  calidum  and  C.  frigidum  also  feed  upon  the  caterpillars, 
and  no  doubt  other  large  ground  beetles  eat  them  also. 

Several  species  of  Dipterous  parasites  have  been  bred  from 
gypsy  caterpillars.  In  19 10,  a  caterpillar  was  observed  at  Wal- 
lingford  with  Tachinid  eggs  on  its  back.  This  caterpillar  pupated 
in  captivity  and  from  the  pupa,  emerged  a  large  two-winged  fly 
Tachina  mclla  Walk.  (See  figure  10).  The  gypsy  moth 
pupa  was  closely  packed  with  the  puparia  of  the  fly  but  only  one 
adult  emerged.  Several  other  Tachinid  flies  have  been  reared 
from  the  gypsy  moth.  Several  Hymenopterous  or  four-winged 
parasitic  flies  have  been  recorded  as  attacking  the  gypsy  moth. 
Three  or  four  species  of  predaceous  bugs  called  "soldier  bugs"  are 
known  to  attack  and  kill  the  caterpillars. 


l8       CONNECTICUT    EXPERIMENT    STATION,    BULLETIN    NO.    l86. 

Though  upwards  of  forty  species  of  birds  have  been  observed 
feeding  upon  the  gypsy  moth  in  its  different  stages,  only  a  few 
species  are  useful  in  destroying  the  pest.  Among  these  are  the 
cuckoos,  oriole,  robin,  catbird,  blue  jay,  crow,  chipping  sparrow, 
chickadee  and  vireos. 

A  wilt  disease  which  has  been  known  for  several  years  and 
which  may  be  indigenous  to  this  country,  kills  many  caterpillars, 
and  especially  during  the  past  two  years,  has  shown  promise. 

As  has  been  stated,  all  the  natural  enemies  occurring  in  New 
England  have  so  far  demonstrated  their  inability  to  control  or  to 
appreciably  check  the  gypsy  moth. 


•Vi '    ;AsiK"  >  ■•  ■-'  ■  "  ■  '■'■ ;  tj^^' 

Figure    14. — Apanteles  lacteicolor,  a  promising  imported  parasite  which 

has  been  brought  into  Connecticut.      (After  Howard  and  Fiske, 

Bureau  of  Entomology,  U.  S.  Dept.  of  Agriculture.) 

Imported  Parasites. 

In  Europe,  however,  the  gypsy  moth  has  not  been  such  a  de- 
structive pest  as  in  this  country  and  is  there  held  in  check  by  its 
natural  enemies.  Beginning-  in  1905,  the  State  of  Massachusetts 
in  co-operation  with  the  Federal  Bureau  of  Entomology,  sought 
to  import  some  of  these  parasites  and  predaceous  insects  as  an 
aid  in  controlling  the  pest  in  the  United  States.  Dr.  L.  O.  How- 
ard made  several  trips  to  Europe  and  enlisted  the  services  of  all 
the  leading  entomologists  of  those  countries  where  the  gypsy 
moth  occurs.     Japan   was  visited   for  the  same  purpose.     Para- 


THE  GYPSY  MOTH!  CONTROL  MEASURES.  10 

sitized  material  was  gathered  in  enormous  quantities  and  sent  to 
the  Parasite  Laboratory  at  Melrose  Highlands,  Mass.,  where  the 
parasites  were  reared  and  studied;  many  species  were  found  to 
be  hyperparasites  and  had  to  be  destroyed.  The  most  promising 
parasites  were  reared  in  large  numbers  and  colonies  were  planted 
in  situations  favorable  for  their  development.  Several  of  these 
have  now  become  established  and  have  successfully  passed  several 
winters. 

Among  the  most  important  of  these  imported  natural  enemies  is 
a  large  purplish  ground  beetle  Calosoma  sycophanta  Linn.,  from 
Europe  which  in  both  its  adult  and  its  larval  stages  feeds  upon  the 
caterpillars  and  pupae  of  the  gypsy  moth.  A  Tachinid  fly  Comp- 
silura  concinnata  Meig.,  from  Europe  attacks  both  gypsy  and 
brown-tail  caterpillars.  Two  egg-parasites,  Anastatus  bifasciatus 
Fonsc.  from  Europe  and  Schedius  kuvance  How.,  from  Japan 
promise  to  become  effective  gypsy  moth  destroyers.  Perhaps  the 
most  important  Hymenopterous  parasite  is  Apanteles  lacteicolor 
Vier.,  which  attacks  the  small  caterpillars  of  both  the  gypsy  and 
the  brown-tail  moths.      (See  figure  14.) 

Of  these  parasites,  Compsilura  concinnata  has  been  planted  at 
six  points  in  Connecticut,  Apanteles  lacteicolor  in  nine  separate 
localities,  and  Calosoma  beetles  have  been  liberated  at  Stonington 
and  at  Thompson.  Apanteles  lacteicolor  has  been  recovered  from 
seven  localities  in  the  winter  nests  of  the  brown-tail  moth. 

It  is  hoped  and  expected  that  in  time  these  parasites  will  mate- 
rially reduce  the  numbers  of  the  gypsy  moth  and  thus  hold  it  in 
check;  but  it  should  be  borne  in  mind  that  parasites  seldom  or 
never  wholly  exterminate  their  hosts.  Until  such  time  as  the 
parasites  demonstrate  their  ability  to  become  a  controlling  factor 
in  the  gypsy  moth  warfare,  we  must  continue  our  work  of  scout- 
ing and  creosoting  the  egg-clusters,  spraying  the  foliage,  and  ap- 
plying tanglefoot  bands  to  the  trees. 

Control  Measures. 

Creosoting1  Egg-Clusters. — Egg-clusters  can  best  be  seen  when 
the  trees  are  bare,  though  they  occur  from  August  1st  to  April 
1st;  therefore  most  of  the  scouting  for  them  is  done  during  the 
winter  months,  especially  when  there  is  no  snow  on  the  ground. 
The  scouts  are  provided  with  field  glasses,  mirrors  and  bark 
knives.     They  must  examine  each  tree  from  all  sides,  look  into  the 


20      CONNECTICUT    EXPERIMENT    STATION',    BULLETIN    NO. 

cavities,  etc.,  and  by  aid  of  the  mirrors  can  examine  the  under  side 
of  fence  rails,  etc.  They  also  earn-  creosote  for  soaking  the 
clusters  to  prevent  hatching.  If  creosote  is  painted  over  the  sur- 
face lightly  there  is  danger  that  some  of  the  eggs  will  escape  in- 
jury and  hatch  :  the  entire  cluster  should  be  well  soaked.  Creosote 
is  a  liquid  which  can  he  obtained  from  nearly  all  hardware  and 
paint  stores,  usually  costing-  about  35  cents  a  gallon,  but  can  he- 
purchased  for  less  in  larger  quantities.  By  adding  to  it  a  small 
proportion  of  lampblack,  the  egg-clusters  are  blackened  so  that  the 


Figure  15. — Examining  fence  and  destroying  egg-clusters. 

treated  clusters  are  easily  distinguished  from  the  untreated  ones 
It  is  seldom  safe  to  scrape  or  otherwise  remove  the  egg-clusters 
from  the  trees,  on  account  of  the  danger  oi  breaking  litem  apart. 
It  is  always  better  to  creosote  them,  without  scattering  them. 

Banding  Trees. —  In  former  years,  applying  burlap  hands  to  the 
trunks  of  trees  as  a  hiding  place  for  the  caterpillars  was  a  common 
practice,  as  well  one  of  the  imp  'riant  methods  ol  control.  In  such 
cases,  it  was  first  necessarj  to  remove  the  dead  wood  from  the 
tree,  fill  the  cavities  with  cement  or  cover  them  with  tin  patches, 
and  scrape  off  the  outer  or  rough  bark,      [n  addition  to  these  re- 


THE  GYPSY  MOTH!  CONTROL  MEASURES.  2  1 

quirements  many  old  apple  trees  had  to  be  thinned  to  let  more  light 
into  their  tops.  All  of  this  work  was  necessary  in  order  to  remove 
all  other  convenient  hiding  places  for  the  caterpillars,  and  to  force 
them  to  go  tinder  the  burlap  bands.  The  bands  are  then  turned 
each  day  and  all  caterpillars  found  under  them  are  destroyed. 
This  method  was  practiced  at  Stonington  and  at  Wallingford  and 
is  especially  adapted  to  exterminative  work  in  isolated  colonies. 
For  this  purpose  8-ounce  burlap  should  be  cut  into  strips  8  inches 


Figure  16. — Method  of  applying  burlap  band. 

wide,  and  a  band  placed  around  the  trunk  of  the  tree  at  a  con- 
venient height  tied  around  the  middle  with  jute  wool-twine,  and 
the  upper  half  of  the  burlap  folded  down  over  the  lower.  This 
makes  a  double  thickness  to  shelter  the  caterpillars.  In  examining 
the  bands,  it  is  a  common  practice,  to  turn  them  up  one  day  and 
down  the  next,  thus  enabling  the  foreman  to  keep  a  check  on  the 
work  of  his  men.  On  account  of  the  danger  of  brown-tail  rash  or 
poisoning  it  is  advisable  not  to  apply  burlap  bands  until  after  the 
middle  of  June,  when  most  of  the  brown-tail  caterpillars  have 
pupated. 


2  2       CONNECTICUT    EXPERIMENT    STATION,    BULLETIN'    NO.     1 86. 

More  recently,  tanglefoot  bands  have  come  into  use  to  prevent 
caterpillars  from  crawling  up  or  clown  a  tree.  If  the  tree  is  sus- 
pected of  being  infested,  then  it  may  be  sprayed  and  a  tanglefoot 
band  placed  around  the  trunk,  thus  compelling  the  caterpillars 
to  feed  upon  the  poisoned  foliage  or  starve.  If  a  tree  is  free  from 
caterpillars,  it  may  be  kept  so  by  the  use  of  the  tanglefoot  band. 
Tree  tanglefoot  is  a  viscid  liquid  or  paste,  which  may  be  purchased 
by  weight  in  quantities  from  one  pound  upwards,  the  cost  varying 
according  to  the  amount  ordered.  The  tanglefoot  material  should 
be  applied  to  form  a  layer,  at  least  one-fourth  of  an  inch  or  more  in 
thickness.  It  hardens  after  a  time,  especially  in  cold  stormv 
weather,  and  it  is  necessary  to  go  over  it  every  week  or  ten  days 
with  a  comb-like  tool  to  render  it  effective. 

Spraying. — One  of  the  most  effective  methods  of  controlling 
this  insect  is  to  thoroughly  spray  the  foliage  with  lead  arsenate 
paste,  using  about  5  pounds  in  50  gallons  of  water.  Half  this 
weight  of  dry  or  powdered  lead  arsenate  can  also  be  used.  On 
orchard  or  other  small  trees  or  shrubs  the  ordinary  orchard  hand 
outfit  may  be  used.  Even  smaller  knapsack  or  bucket  pumps  may 
be  used  in  the  home  garden.  But  for  spraying  a  large  number  of 
tall  shade  trees  along  the  street  or  highway,  or  in  woodland  areas, 
more  powerful  pumps  are  more  economical.  There  are  now  on 
the  market  gasoline  power  outfits  with  10-horse  power  engines 
that  will  throw  a  solid  stream  into  the  tops  of  the  tallest  trees,  the 
stream  then  breaking  into  a  spray.  Such  an  outfit,  of  course, 
uses  more  liquid  but  saves  in  labor,  and  enables  one  to  spray  the 
ordinary  woodland  areas  at  a  cost  of  six  or  seven  dollars  per  acre, 
where  formerly  the  cost  was  prohibitive  often  amounting  to  fifty 
or  seventy-five  dollars  per  acre.  For  this  kind  of  work  the  pres- 
sure should  be  above  200  pounds. 

Summary. 

Distribution. — The  gypsy  moth  occurs  in  Central  and  Southern 
Europe  and  Asia  and  Northern  Africa,  and  though  it  causes  great 
damage  in  some  of  the  countries,  on  account  oi  its  natural  ene- 
mies, it  is  not  such  a  pest  there  as  in  the  New  England  States 
where  it  has  caused  millions  of  dollars  damage.  It  was  brought 
into  Massachusetts  about  [869  in  an  attempt  to  cross  it  with  silk 
worms  to  produce  a  hardy  race  of  the  latter.  Some  individuals 
escaped  from  the  breeding  cages  in   Medford.  Mass..  and  twenty 


THE    GYPSY   MOTH!     SUMMARY.  23 

years  later  was  such  a  pest  there  that  the  town,  and  later  the 
State,  appropriated  funds  for  its  suppression.  State  work  was 
kept  up  for  ten  years,  but  in  1900  was  discontinued.  In  1905  it 
was  again  resumed,  after  the  pest  had  spread  over  more  than  six 
times  the  area  formerly  infested.  In  1906  Congress  appropriated 
money  to  aid  the  New  England  States  and  the  Bureau  of  Ento- 
mology has  since  co-operated  in  the  control  work. 

The  gypsy  moth  now  covers  more  than  half  of  the  State  of 
Massachusetts  (eastern  portion),  the  southwest  corner  of  Maine, 
nearly  half  of  New  Hampshire  (the  southeastern  part),  the  whole 
of  Rhode  Island,  eighteen  towns  in  the  eastern  end  of  Connecti- 
cut, and  it  has  just  been  discovered  in  Vermont.  Isolated  colonies 
elsewhere  have  also  been  found  at  Lenox,  Stockbridge  and  Great 
Barrington,  Mass. ;  at  Wallingford,  Conn. ;  at  Geneva  and  Mt. 
Kisco,  N.  Y. ;  near  Cleveland,  Ohio;  and  at  Rutherford,  N.  J.,  all 
of  which  have  been  practically  eradicated. 

The  pest  was  first  discovered  in  Connecticut  at  Stonington  in 
1906,  where  an  isolated  infestation  of  less  than  one  square  mile  in 
extent  was  found  to  exist.  Control  measures  were  inaugurated 
by  the  Station  and  continued  until  the  colony  was  exterminated 
in  1911. 

Another  colony  was  found  in  Wallingford  in  December  1909, 
and  similarly  eradicated  in  1913. 

In  the  spring  of  191 3,  newly  hatched  caterpillars,  were  brought 
into  the  border  towns  of  Connecticut  presumably  by  a  gale  from 
the  East.  The  first  caterpillars  were  found  by  State  employees  at 
Stonington,  and  in  order  to  learn  where  they  came  from,  Federal 
scouts  began  to  examine  the  surrounding  country,  and  to  search 
the  towns  along  the  border.  Up  to  this  time  eighteen  towns, 
named  on  page  9  and  shown  on  the  map,  figure  2,  have  been 
found  infested. 

A  Federal  quarantine  has  been  established  covering  the  large  in- 
fested contiguous  territory.  All  nursery,  forest  and  quarry  pro- 
ducts must  be  inspected  and  certified  by  a  Federal  inspector  before 
they  can  be  shipped  outside  of  this  area. 

Food  Plants  and  Damage. — The  gypsy  caterpillars,  when  large, 
feed  upon  nearly  all  kinds  of  vegetation  including  conifers,  which 
if  stripped  soon  die :  newly  hatched  caterpillars  require  some  other 
food.  Ash  is  perhaps  the  most  nearly  immune  of  all  the  decid- 
uous trees. 


24      CONNECTICUT    EXPERIMENT    STATION,    BULLETIN    NO.     [86. 

Methods  of  Spread. — Gypsy  moths  are  spread  as  follows:— 
Egg-clusters  arc  transported  in  many  ways;  caterpillars  carried 
on  vehicles;  newly  hatched  caterpillars  arc  blown  in  a  strong 
wind.  The  former  method  accounts  for  most  of  the  isolated  col- 
onies, and  the  latter  may  explain  the  increase  in  the  area  of 
long-standing  infestations. 

Life  History, — Egg-clusters  laid  in  summer  hatch  the  following 
spring,  and  the  caterpillars  become  fully  grown  about  the  first  of 
July.  They  then  go  into  protected  places  and  transform  to  the 
pupa  stage.     From  ten  to  fourteen  days  later  the  adults  emerge. 

The  female  is  a  large-bodied  whitish  moth,  with  wing-spread  of 
more  than  two  inches:  she  cannot  fly  but  laws  on  tree,  fence,  wall 
or  building-,  masses  containing  400  or  more  globular  eggs.  The 
male  is  smaller  and  darker  in  color  and  flies  about.  The  mature 
caterpillars  are  between  two  and  three  inches  long,  dark  gray  or 
brown,  and  hairy.  A  narrow  light  stripe  extends  along  the  back 
with  a  row  of  tubercles  on  each  side.  Each  tubercle  bears  light 
brown  hairs.  From  the  head  backward  the  first  five  pairs  of 
tubercles  are  blue  and  the  remaining  six  pairs  brick-red.  Tin- 
chrysalis  is  a  naked  brown  pupa  fastened  loosely  by  a  few  strands 
of  silk. 

Natural  Enemies. — Native  birds  such  as  cuckoos,  oriole,  robin, 
vireos,  etc.,  feed  upon  the  caterpillars.  There  are  several  preda- 
ceous  insects,  including  the  large  ground  beetles  and  die  "soldier 
bugs"  which  destroy  limited  numbers.  A  few  native  two-winged 
and  four-winged  flies  are  parasites,  but  all  of  these  agencies  to- 
gether do  not  keep  the  pest  in  check.  All  insect  enemies  of  the 
gypsy  moth  that  can  be  found  throughout  its  range  have  been 
brought  from  the  ( )ld  World  to  New  England.  (  )f  these,  a  large 
ground  beetle  Calosoma  sycophanta,  a  Tachinid  fly  Compsilura 
concinnata  and  two  four-winged  parasitic  Hies  Apanteles  la 
color  and  Anastatus  bifasciatus  have  shown  great  effectiveness. 
have  withstood  our  climate  and  multiplied,  and  have  been  liberated 
in  the  infested  territory,  including  Connecticut. 

Control  Measures. — The  chief  control  measures  are  creosoting 
the  egg-clusters,  spraying  the  foliage  with  lead  arsenate,  applying 
tanglefoot  bands  to  the  trunks  of  trees,  and  thinning  the  woodland 
U  1  leave  a  resistant  sti  >wth. 


Hie  Wilson  H.Lee  Co.,  New  Haven.  Conq 


University  of 
Connecticut 

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